As their name implies, “Super 3G” mobile telecommunications networks are intended to provide improvements over today's 3G mobile telecommunications networks. One such improvement being targeted is a tenfold improvement of the existing 3G data rate meaning Super 3G networks should provide a target data rate in the downlink direction of 100 Mbps and for in the uplink direction of 50 Mbps. It is expected that services available in future Super 3G mobile telecommunications networks shall be similar to the existing 3G HSDPA (High Speed Downlink Packet Access), MBMS (Multimedia broadcast-multicast services) and HSUPA (High Speed Uplink Packet Access) service but with significantly higher data rates.
In order to achieve such a high data rate in Super 3G networks a new radio access technology-orthogonal frequency division multiplexing (OFDM) has been introduced together with higher modulation (64-QAM) and using turbo or LDPC (low density parity check) coding schemes as well as other features such as multiple input multiple output (MIMO). OFDM is a modulation technique that can be used for high speed data communication, whose main idea is to send data in parallel over a number of spectrally overlapping orthogonal sub-channels.
OFDM is considered to have the certain advantages over other radio access technologies, including the following:                High spectral efficiency can be obtained by a careful selection of the frequencies for the so-called sub-carriers, by defining the frequency spacing between sub-carriers equal to the reciprocal of the OFDM symbol duration.        OFDM has superior power efficiency over other technologies as there is no crowding in signal space.        OFDM can be made robust to multi-path interference by introducing guard interval in between consecutive OFDM symbols in the time domain.        OFDM is robust to narrow band interference.        
However, OFDM is quite sensitive to impairments such as phase noise, carrier frequency offset, I/Q imbalance, phase distortion and linearity issues, which can introduce inter-carrier interference, reduce SINR (Signal to Interference and Noise Ratio) and create intermodulation problems. These identified impairments always exist in implementations of OFDM and affect the ability to apply higher level modulation schemes and coding schemes, therefore making it more difficult to achieve the target data rates discussed above. Moreover they are also expensive to mitigate or reduce.